Age Estimation in Brazilian Adults Using the Pulp/Tooth Ratio of the Maxillary Canine and Mandibular Second Premolar.

(1) Background/Objectives: Accurate determination of chronological age is crucial in legal dental identification. This study aimed to compare the effectiveness of different formulas in estimating the age of a Brazilian subpopulation by analyzing the pulp/tooth ratio of the maxillary canine and mandibular second premolar in panoramic and periapical radiographs. (2) Methods: The sample consisted of panoramic and periapical radiographs of 247 individuals. The file of each radiograph was opened in the Adobe Photoshop CS4® program to outline and obtain values in pixels for calculating the pulp/tooth ratio. Statistical analysis was conducted using the SPSS program, with a significance level set at 5%. (3) Results: The interclass correlation coefficient demonstrated excellent intra-observer agreement (0.990-0.999). The determination coefficients (R2) suggested that only 30-35% of the actual age results could be explained by the pulp/tooth ratio. The smallest differences were observed with Cameriere's formula for the mandibular second premolar on panoramic radiographs (+4.1 years). The greatest differences were found with the formulas for the mandibular second premolar in panoramic radiographs of the Korean (+12.5 years) and Portuguese (-12.1 years) populations. (4) Conclusions: The equations employed showed little agreement between the actual age and the estimated age.

Adhesion and sealing of different universal adhesive systems associated with bulk-fill resins after using endodontic irrigation solutions: An in vitro study.

This study aimed to evaluate the interface of universal adhesive (UA) with bulk-fill resin (BF) and dentin, after endodontic irrigation. The pulp chamber of 96 molars was irrigated with chlorhexidine 2% (CHX) or sodium hypochlorite 5.25% (NaOCl) and restored according to three restorative protocols. Microtensile bond strength (µTBS) and nanoleakage tests were performed after 24 h of thermocycling. Kruskal Wallis, Mann-Whitney and Wilcoxon were performed (p < 0.05). Comparing restorative systems, a difference was found only when irrigated with CHX after 24 h. CHX provided higher µTBS than NaOCl after 24 h for two restorative protocols; after thermocycling, NaOCl provided the greatest µTBS than CHX for one group. Decreased µTBS was observed for all restorative systems when CHX was used after thermocycling. NaOCl demonstrated the highest nanoleakage. The composition of UA influenced the immediate adhesion and sealing to BF when CHX was used; ageing has a deteriorating effect on adhesion and sealing for all restorative systems.

A systematic review and meta-analysis on the effects of phototherapy on postoperative pain in conventional endodontic reintervention.

OBJECTIVES: This systematic review and meta-analysis (SRM) aimed to evaluate the efficacy of laser phototherapy (LPT) on the reduction in postoperative pain (PP) of endodontic origin after conventional/non-surgical reintervention of root canals. METHODS: This SRM was registered with PROSPERO (CRD42021243500) and followed the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis. Meta-analysis was conducted using R software with the "META" package, the mean difference (MD) measure of effect was calculated, and the fixed effect model was applied with a 95% confidence interval (CI). The Cochrane collaboration scale was used to assess the risk of bias and the GRADE tool to assess the quality of evidence. RESULTS: Initially, 1028 articles were found, and five articles were included. Most studies were classified as "low" risk of bias. Of the five clinical studies, four showed a significant decrease in PP after endodontic reintervention in the LPT groups compared to the control group, especially in the first four days after the intervention. In symptomatic teeth with multiple roots, LPT led to less PP at 24 h (MD -0.52 [-1.03; -0.02] p = .04). However, no significant difference between the groups was found at 48 and 72 h (p > .05). The certainty of the evidence was classified as low. CONCLUSION: Despite the limitations of this SRM, LPT was shown to be a promising alternative for reducing and controlling PP in conventional endodontic reintervention. CLINICAL SIGNIFICANCE: The use of LPT in endodontic reintervention may be a safe and promising alternative to clinically efficacious agent for use in the management of PP in this procedure.

The impact of methylene blue photosensitizer, aPDT and a calcium hydroxide-based paste on the physicochemical and mechanical characteristics of root canal dentin and the bonding interface of fiberglass posts.

PURPOSE: To investigate the influence of methylene blue (MB)-mediated antimicrobial photodynamic therapy (aPDT) and calcium hydroxide (CH) medication on the mechanical characteristics, degree of conversion (DC), quantification, and volume of gaps at the adhesive interface of glass fiber posts (GFPs) luted to distinct thirds of root canal dentin. Additionally, the microhardness (MH), elastic modulus (Eit), morphology, and chemical structure of the intraradicular dentin were assessed. MATERIALS AND METHODS: 6 experimental groups were formed by sorting 102 bovine incisors. Canals receiving deionized water irrigation as a negative control; canals receiving deionized water irrigation and filled with CH as a positive control; groups treated with CH + MB at 50 and 100 mg/L without irradiation; and groups treated with CH + MB at 50 and 100 mg/L irradiated by red laser for 60 s (660 nm; 100 mW; 6.5 J; 72 J/cm2). MH, Eit, and DC properties were evaluated for both the resin cement layer and root dentin substrate (n = 8). Volume and quantification of gaps at the bonding interface (n = 6), and dentin morphology and chemical content were investigated (n = 3). Data were analyzed using a repeated-measures 2-way ANOVA followed by Tukey post hoc analysis (α = 0.05). RESULTS: The distinct intraradicular thirds and treatment with MB-mediated aPDT, whether activated or not, in combination with CH, had a significant impact on the mechanical characteristics of the root dentin. This effect was also observed in the MH, Eit, DC, quantification, and volume of gaps at the luting interface (P < .05). In general, a higher concentration of MB, whether activated by a red laser or not, led to lower values in the mechanical properties of the root dentin, as well as in MH, Eit, and DC at the adhesive interface (P < .05). Additionally, these groups exhibited higher values for quantification and volume of gaps at the luting substrate (P < .05). Scanning electron micrographs and energy dispersive X-ray spectra showed qualitative similarity among all groups, except for the negative experimental control group. CONCLUSIONS: MB-mediated aPDT at 50 mg/L, in combination with CH, demonstrated favorable physico-chemical and mechanical characteristics in intraradicular dentin, along with satisfactory mechanical features and the adhesive interface integrity for GFPs at all intraradicular depths. CLINICAL SIGNIFICANCE: MB-mediated aPDT at a concentration of 50 mg/L combined to CH medication represents a suitable choice for photosensitization in the context of intracanal disinfection following the biomechanical procedure and prior to luting of intraradicular restorations.

Influence of systemic antibiotic therapy on the development and progression of induced apical periodontitis in Wistar rats.

The aim of this study was to investigate the influence of systemic antibiotic therapy on the development and progression of induced apical periodontitis (AP) in Wistar rats. Fifty-six rats were submitted to pulp exposure of the lower left first molar for the induction of AP. On the same day, intraperitoneal antibiotic therapy was administered once a day, for 15 days, until euthanasia. The groups were formed according to the different treatments (n = 8): C-control; GEN-treated with gentamicin (10 mg/Kg); AC-treated with amoxicillin (100 mg/Kg); MZ-treated with metronidazole (40 mg/Kg); AMP-treated with ampicillin (100 mg/Kg); AMC group-treated with amoxicillin + clavulanic acid (100 mg/kg); CLI-treated with clindamycin (60 mg/kg). After euthanasia, the jaws were collected and processed for (1) histological and histometric analysis using hematoxylin and eosin staining, (2) analysis of collagen fibers using Picrosirius Red staining and (3) bacteriological analysis using Brown-Brenn staining. The data were analyzed statistically (p < 0.05). AP induction was confirmed in all groups. The AMC group had the lower intensity of inflammatory infiltrate (p = 0.028) and less periapical bone resorption compared to control (p = 0.006). Regarding collagen maturation, PSR staining revealed a predominance of mature collagen fibers in all groups. The AC and AMC groups had the lower amount of mature fibers and the highest amount of immature fibers, compared to all other groups (p < 0.001). All groups showed bacterial contamination; however, the AC and AMC groups showed a lower extent of bacterial contamination compared to the control (p < 0.001). It can be concluded that systemic antibiotic therapy influences the development and progression of induced AP.

Influence of dental bleaching on the pulp tissue: A systematic review of in vivo studies.

BACKGROUND: Although several studies indicate the harmful effects of bleaching on pulp tissue, the demand for this procedure using high concentrations of hydrogen peroxide (HP) is high. OBJECTIVES: To investigate the influence of bleaching on the pulp tissue. METHODS: Electronic searches were conducted (PubMed/MEDLINE, Scopus, Cochrane Library and grey literature) until February 2021. Only in vivo studies that evaluated the effects of HP and/or carbamide peroxide (CP) bleaching gels on the inflammatory response in the pulp tissue compared with a non-bleached group were included. Risk of bias was performed according to a modified Methodological Index for Non-Randomized Studies scale for human studies and the Systematic Review Centre for Laboratory Animal Experimentation's RoB tool for animal studies. Meta-analysis was unfeasible. RESULTS: Of the 1311 studies, 30 were eligible. Of these, 18 studies evaluated the inflammatory response in animal models. All these studies reported a moderate-to-strong inflammatory response in the superficial regions of pulp, characterized by cell disorganization and necrotic areas, particularly during the initial periods following exposure to 35%-38% HP, for 30-40 min. In the evaluation of human teeth across 11 studies, seven investigated inflammatory responses, with five observing significant inflammation in the pulp of bleached teeth. In terms of tertiary dentine deposition, 11 out of 12 studies noted its occurrence after bleaching with 35%-38% HP in long-term assessments. Additionally, three studies reported significant levels of osteocalcin/osteopontin at 2 or 10 days post-treatment. Other studies indicated an increase in pro-inflammatory cytokines ranging from immediately up to 10 days after bleaching. Studies using humans' teeth had a low risk of bias, whereas animal studies had a high risk of bias. DISCUSSION: Despite the heterogeneity in bleaching protocols among studies, High-concentrations of HP shows the potential to induce significant pulp damage. CONCLUSIONS: High-concentrations of bleaching gel increases inflammatory response and necrosis in the pulp tissue at short periods after bleaching, mainly in rat molars and in human incisors, in addition to greater hard tissue deposition over time. However, further well-described histological studies with long-term follow-up are encouraged due to the methodological limitations of these studies. REGISTRATION: PROSPERO (CRD42021230937).

Final irrigation with bioglass solution in regenerative endodontic procedure induces tissue formation inside the root canals, collagen maturation, proliferation cell and presence of osteocalcin.

AIM: To evaluate the influence of an experimental solution of cobalt-doped F18 bioactive glass (F18Co) on tissue repair following regenerative endodontic procedure (REP) in rat molars. METHODOLOGY: The F18Co solution was prepared at a ratio of 1:5 F18Co powder to distilled water. The right or left upper first molars of 12 Wistar rats were used, where the pulps were exposed, removed, and irrigated with 2.5% sodium hypochlorite (NaOCl), followed by 17% ethylenediaminetetraacetic acid (EDTA) (5 min each). Subsequently, the molars were divided into two groups (n = 6): REP-SS and REP-F18Co, where they received a final irrigation (5 min) with saline solution (SS) or F18Co solution, respectively. Then, intracanal bleeding was induced, and the tooth was sealed. Untreated molars were used as controls (n = 3). At 21 days, the rats were euthanized, and the specimens were processed for analysis of mineralized tissue and soft tissue formation inside the root canal using haematoxylin-eosin. The presence and maturation of collagen were evaluated by Masson's trichrome and picrosirius red staining. Immunolabelling analyses of proliferating cell nuclear antigen (PCNA) and osteocalcin (OCN) were performed. The data were submitted to the Mann-Whitney U-test (p < .05). RESULTS: There was a similar formation of mineralized tissue in thickness and length in REP-SS and REP-F18Co groups (p > .05). Regarding the presence of newly formed soft tissue, most specimens of the REP-F18Co had tissue formation up to the cervical third of the canal, whilst the REP-SS specimens showed formation up to the middle third (p < .05), and there was higher maturation of collagen in REP-F18Co (p < .05). The number of PCNA-positive cells found in the apical third of the root canal was significantly higher in the F18Co group, as well as the OCN immunolabelling, which was severe in most specimens of REP-F18Co, and low in most specimens of REP-SS. CONCLUSION: The final irrigation with F18Co bioactive glass solution in REP did not influence mineralized tissue formation but induced soft tissue formation inside the root canals, with higher collagen maturation, and an increase in PCNA-positive cells and OCN immunolabelling.

Influence of bioceramic sealers on dentinal tubule penetration and antimicrobial effectiveness: a systematic review and meta-analysis of in vitro studies.

The aim of this systematic review and meta-analysis (SRM) was to evaluate whether bioceramic sealers have better penetration capacity in dentinal tubules and antimicrobial activity when compared to AH Plus® sealer. This SRM was recorded in the Open Science Framework database and followed the guidelines of the PRISMA 2020. Five databases were searched by two independent reviewers. Only in vitro studies that evaluated the effects of bioceramic sealers on dentinal tubule penetration and antimicrobial activity outcomes compared to AH Plus® sealer were included. Meta-analysis was conducted using R software, using the effect measure of the standardized mean difference (SMD) and inverse variance method. A modified Joanna Briggs Institute's Checklist was used for the risk of bias assessment. A total of 1486 studies were identified, and only 54 studies that fulfilled our eligibility criteria were included in this review. There was no statistical difference between the sealers evaluated for dentinal tubule penetration, in the thirds evaluated: coronal SMD 0.58 [0.14; 1.31], p = 0.12; middle SMD 0.07 [0.54; 0.39], p = 0.75; and apical SMD 0.08 [0.73; 0.56], p = 0.80. Both sealers demonstrated similar antimicrobial action (SMD [3.42; 5.32], p = 0.67 and SMD 0.67 [1.89; 0.55], p = 0.28). The studies presented a low risk of bias. Based on the in vitro studies included and according to the limitations of the present review, the data suggest that bioceramic and AH Plus® sealers present similar penetration capacity in dentinal tubules and antimicrobial effect, making them suitable materials to be considered in clinical practice.

Experimental apical periodontitis alters salivary biochemical composition and induces local redox state disturbances in the salivary glands of male rats.

OBJECTIVES: The objective was to evaluate the effects of experimental apical periodontitis on the inflammatory, functional, biochemical, and redox parameters of the parotid and submandibular glands in rats. MATERIALS AND METHODS: Twenty 12-week-old male Wistar rats were randomly divided into two groups (n = 10): a control group and apical periodontitis group. After 28 days, the saliva was collected for salivary flow rate and biochemistry composition. Both glands were sampled for quantification of the tumor necrosis factor-alpha (TNF-α) and biochemical analyses of redox state. RESULTS: TNF-α concentrations were higher in both salivary glands adjacent to the periapical lesions in animals with apical periodontitis and also compared to the control group. The apical periodontitis group increased the salivary amylase, chloride, potassium, calcium, and phosphate. The total oxidant capacity increased in the parotid gland adjacent to the periapical lesions in the same rat and compared to the control group. Conversely, the total antioxidant capacity of the parotid glands on both sides in the apical periodontitis group was lower than that in the control group. Furthermore, glutathione peroxidase activity increased in the submandibular gland adjacent to the apical periodontitis group compared to the control group. CONCLUSIONS: Experimental apical periodontitis alters salivary biochemical composition, in addition to increasing inflammatory marker and inducing local disturbances in the redox state in the parotid and submandibular glands of male rats. CLINICAL RELEVANCE: Apical periodontitis could exacerbate the decline in oral health by triggering dysfunction in the salivary glands.

Influence of photoactivation on tissue response to different dyes used in photodynamic therapy and laser ablation therapy.

Laser ablation therapy (LA) uses Indocyanine Green dye (ICG) which efficiently absorbs laser energy and the increased temperature results in an instantaneous flame that chars tissue and microbes. Photodynamic therapy (PDT) uses different dyes that are activated by light to kill bacteria. This study evaluated the biocompatibility of the dye Curcumin (CUR), Methylene Blue (MB), and Indocyanine Green (ICG) before and after laser activation (ACT). Polyethylene tubes containing one of the dyes were implanted in the subcutaneous tissue of 32 rats (4 tubes per rat) which were divided into 8 groups: C - control (saline solution); C + ACT (Red Laser 660 nm); CUR; CUR + ACT (480 nm blue LED); MB; MB + ACT (Red Laser 660 nm); ICG; ICG + ACT (810 nm Infrared Laser). After 7 and 30 days (n = 8/time), the rats were euthanized and the tubes with the surrounding tissue were removed and processed for histological analysis of inflammation using H&E stain, and collagen fiber maturation using picrosirius red (PSR). A two-way analysis of variance statistical test was applied (p < 0.05). At 7 days, regardless of laser activation, the CUR group showed a greater inflammatory infiltrate compared to the ICG and control groups, and the MB group had a greater inflammation only in relation to the control (p < 0.05). At 30 days, CUR and MB groups showed a greater inflammatory infiltrate than the control (p < 0.05). ICG group was equal to the control in both periods, regardless of the laser activation (p > 0.05). Laser activation induced the proliferation of collagen immature fibers at 7 days, regardless of the dye (p < 0.05). The CUR group showed a lower percentage of immature and mature fibers at 7 days, compared to ICG and control (p < 0.05) and, at 30 days, compared to control (p < 0.05). Regardless of laser activation, the ICG showed the results of collagen maturation closest to the control (p > 0.05). It was concluded that all dyes are biocompatible and that laser activation did not interfere with biocompatibility. In addition, the maturity of collagen was adequate before and after the laser activation. These results demonstrate that the clinical use of dyes is safe even when activated with a laser.

Bone Resorption in Apical Periodontitis Enhanced by Cigarette Smoke Inhalation: Histometric, Immunohistochemical, and Microtomographic Analysis in Rats.

INTRODUCTION: This study evaluated the effects of cigarette smoke inhalation (CSI) on apical periodontitis (AP) induced in rats by histometric, immunohistochemical, and microtomographic analysis. METHODS: A total of 32 male Wistar rats were divided into 4 experimental groups (n = 8): control, CSI, AP, and CSI + AP. Rats in the CSI and CSI + AP groups inhaled cigarette smoke by remaining inside a smoking chamber for 8 minutes 3 times a day for 50 days. After 20 days of smoke inhalation, rats in the AP and CSI + AP groups had the pulp of their first right lower molar exposed to induce AP. Blood was collected on day 50 to evaluate nicotine and serum cotinine levels. The animals' mandibles were removed for histologic processing to evaluate bone resorption by histometric, immunohistochemical (receptor activator of nuclear factor kappa B ligand/osteoprotegerin), and microtomographic analysis. The Student t test was applied. RESULTS: Histometric analysis showed a larger area of bone resorption (P < .05) and microtomographic analysis found greater resorption volume (P < .001) for the CSI + AP group compared with the AP group. The CSI + AP group presented a high RANKL immunostaining pattern compared with the AP group (P < .001). CONCLUSIONS: CSI increased bone resorption caused by AP.

Effect of ELVAX polymer subgingival implants with echistatin on extracted and reimplanted rats' teeth.

To investigate the effect of ELVAX polymer subgingival implants incorporated with echistatin peptide on incisor reimplanted tooth in rats. Forty-two male Wistars rats were divided into two groups: echistatin-treated rats (E) and control rats (C). The animals had their right maxillary incisors extracted and treated according to the International Association of Dental Traumatology replantation protocol. The extra-alveolar dry period was 30 and 60 min, and the post-surgical experimental periods were 15, 60, and 90 days. The samples were stained with H&E and analyzed for the presence of an inflammatory response, incidence of resorptions, and dental ankylosis. Results were statistically analyzed (p < 0.05). The presence of inflammatory resorption was significantly higher in group C at 30 and 60 min extra-alveolar time, in the 15-day postoperative period as compared with the E group (p < 0.05). Dental ankylosis was significantly more prevalent in group E in 30 min extra-alveolar time and 15 days postoperative period (p < 0.05). However, in 60 min extra-alveolar time and 60 days postoperative period, dental ankylosis was more prevalent in C group (p < 0.05). The use of ELVAX subgingival implants with echistatin demonstrated therapeutic potential in preventing the experimental resorption process after replantation of maxillary incisors in rats.

Prevalence of apical periodontitis and non-retention of root-filled teeth in hypertensive patients: Systematic review and meta-analysis.

BACKGROUND: Several studies have suggested a relationship between AP, as well as the loss of root-filled teeth (RFT), and hypertension (HTN). OBJECTIVES: The aims of this systematic review and meta-analysis were to investigate the prevalence of AP, and non-retention of RFT, in hypertensive patients. METHODS: A search was performed in PubMed/MEDLINE, Web of Science, Scopus and EMBASE. The inclusion criteria established were studies published until February 2023, comparing hypertensive subjects with controls, assessing the prevalence of AP and/or providing data on the prevalence of non-retained RFT. Meta-analysis was performed using the RevMan (analyst) tool to determine the pooled prevalence of AP and loss of RFT. Risk of bias was assessed using the Cochrane Risk-of-Bias tool. The quality of evidence was assessed by GRADE. RESULTS: The search strategy identified 454 articles, and only eight met the inclusion criteria. Six studies had analysed the association between AP and HTN and two studies had analysed the association between non-retention of RFT and HTN. Meta-analysis showed and overall OR = 1.71 (95% CI = 0.92-3.16; p = .09) for the prevalence of AP among patients with HTN. The prevalence of non-retention of RFT among patients with HTN has an overall OR = 1.78 (95% CI = 1.60-1.98; p = .000001). The risk of bias in the individual studies was low or moderate, and the quality of the overall evidence has shown a level of certainty very low. DISCUSSION: There is no association between the prevalence of AP and HTN. In addition, hypertensive patients have significantly increased odds of losing RFT. Given the high prevalence of hypertension, it is very common to perform root canal treatments on hypertensive patients. It is imperative to communicate this heightened risk to patients and recommend periodic monitoring of oral health and hypertension, paying special attention to this subset of patients. REGISTRATION: PROSPERO CRD42022302385.

Bleaching gel volume influences hydrogen peroxide diffusion, inflammation, and the presence of nitric oxide in the pulp tissue: in vitro and in vivo model.

OBJECTIVE: To assess whether bleaching gel volume influences chromatic changes, hydrogen peroxide (HP) diffusion, inflammation, and oxidative stress in the pulp tissue. METHODOLOGY: A total of 60 bovine teeth were divided into four groups, according to bleaching gel volume (n=15): without gel (WG); V30 (30 µL of 35% HP); V60 (60 µL); and V120 (120 µL). HP diffusion analysis was performed in the first session (T1). Chromatic changes (ΔE, ΔE00, and WID) were assessed after the first (T1), second (T2), third (T3) sessions, and 15 d (T4) after the end of treatment. Moreover, 20 rats were randomly divided into four groups (n=10) and their upper first molars were treated with different gel volumes: control (no treatment); V2 (2 µL of 17.5% HP); V4 (4 µL); and V8 (8 µL). After 24 h, rats were euthanized and the specimens processed for histological and immunohistochemical (nitric oxide synthase) evaluation. Data were analyzed using the Wilcoxon and Mann-Whitney tests (p<0.05). RESULTS: In vitro (bovine teeth), chromatic changes were not influenced by bleaching gel volume, showing similar values in all groups and sessions, except for the control group (p<0.05). The V120 group had the highest HP diffusion values (p<0.05). In vivo (pulp tissue), the V4 and V8 groups showed the highest inflammatory infiltrate in the pulp and significant oxidative stress (p<0.05). CONCLUSION: The adverse effects on the dental pulp related to HP diffusion, pulp inflammation, and oxidative stress depend on bleaching gel volume, while the bleaching effect is not proportional to the volume used.

Biocompatibility, Biomineralization and Induction of Collagen Maturation with the Use of Calcium Hydroxide and Iodoform Intracanal Dressing.

Biocompatibility and biomineralization of root canal dressings are important requirements for periapical healing. This study evaluated the inflammatory response, biomineralization and tissue repair by collagen fiber maturation in the subcutaneous tissue of rats. Eighteen Wistar rats (n = 6) received subcutaneous implants: calcium hydroxide + propylene glycol [CH+P], calcium hydroxide + propylene glycol + iodoform [CH+P+I], iodoform + carbowax [I+Cwax] and carbowax [Cwax]. Extra empty tubes were used as a control [C]. After 7, 15 and 30 days, the implants were removed with surrounding tissue for staining of hematoxylin-eosin, Von Kossa, picrosirius red and without staining for analysis under polarized light. Results were analyzed via Kruskal-Wallis followed by Dunn testing for nonparametric data and ANOVA followed by a Tukey post hoc test for parametric data (p < 5%). At 7 days, all groups showed a moderate inflammatory reaction and thick fibrous capsule, except the [Cwax] group, with a severe inflammatory infiltrate (p < 0.05). After 15 days, all groups but control had a decrease in inflammatory response. At 30 days, all groups presented a mild reaction and thin fibrous capsule (p > 0.05). Only groups containing calcium hydroxide were found to be positive using Von Kossa staining and polarized light in all periods. At 7 days, all groups showed a higher proportion of immature fibers. At 15 days, the [CH+P] and [Cwax] groups increased their proportion of mature/immature fibers. At 30 days, only the [CH+P] group presented a significant prevalence of mature collagen fibers (p < 0.05). All groups showed biocompatibility, but only groups containing calcium hydroxide induced biomineralization. The addition of iodoform delayed tissue healing.

Effects of cigarette smoke inhalation on the immune-inflammatory profile of experimental apical periodontitis in rats.

OBJECTIVE: To evaluate the effects of cigarette smoke inhalation on the immune-inflammatory profile of experimental apical periodontitis in rats. METHODOLOGY: In total, 32 male Wistar rats were divided into four groups (n = 8): AP-induced apical periodontitis; S-cigarette smoke inhalation; APS-induced AP and cigarette smoke inhalation; and C (control)-neither AP nor cigarette smoke inhalation. To induce cigarette smoke inhalation, the animals were kept in a chamber filled with tobacco smoke for 8 min thrice a day for 50 days. AP was induced 20 days after inhalation initiation by exposing their coronary pulp to their oral environment for 30 days. After animals were euthanized, their right hemimaxillae were removed for histopathological, semi-quantitative and immunohistochemical (F4/80, CD206 and iNOS) analyses. RESULTS: Quantitative data showed a moderate number of inflammatory infiltrates in AP and an intense number in APS (p < .05). Comparing F4/80+ cells showed no statistically significant differences among groups, but we found more CD206+ cells in AP than in C and S (p > .05). INOS+ immunostaining showed a significant increase in AP and APS, when compared with C and S (p < .05). APS had more iNOS+ cells than AP (p < .05). CONCLUSION: Cigarette smoke inhalation worsened AP, leading to a predominantly pro- inflammatory profile in our experimental model.

Evaluation of Serum Levels of Cytokines in Acute Apical Abscess: A Longitudinal Observational Study.

INTRODUCTION: Cytokine levels are related to the aethiopathogenia of acute apical abscesses (AAA); however, the specific cytokine profiles in these cases are unclear. This study aimed to investigate the changes in systemic cytokine levels in patients with AAA and trismus onset, postantibiotic treatment, and postroot canal disinfection. METHODS: In total, 46 AAA patients with trismus and 32 control subjects were included. After seven days of antibiotic therapy, root canal disinfection was performed in the AAA patients. The serum levels of cytokines were evaluated at basal, seven, and 14 days after endodontic treatment. Quantification of cytokines from T helper (Th) 1, Th2, Th17, and regulatory T cells profiles was determined using the BioPlex MagPix system, and the obtained data were analyzed using SPSS statistical software (P < .05). RESULTS: AAA patients showed higher tumor necrosis factor-alpha (TNF-α), interleukin (IL) -6, and IL-10 levels than control subjects, at basal measurement (P < .05); there were similar levels of interferon gamma, IL-1ß, IL-4, and IL-17 between groups (P > .05). IL-6 and IL-10 levels decreased after antibiotic treatment (P < .05), which was also associated with clinical improvement in patients with AAA and trismus. Patients with AAA had a positive correlation with higher serum levels of IL-6 and IL-10. In addition, TNF-α levels decreased only after antibiotic and endodontic treatment. CONCLUSIONS: In conclusion, patients with AAA had increased systemic serum levels of TNF-α, IL-6, and IL-10. Moreover, increased levels of IL-6 and IL-10 are associated with acute inflammatory symptoms. However, IL-6 and IL-10 levels decreased after antibiotic treatment, while TNF-α levels decreased after antibiotic and endodontic treatment.

Biological investigation of resinous endodontic sealers containing calcium hydroxide.

The purpose of this study was to evaluate, in vivo, the biocompatibility, biomineralization, collagen maturation and the in vitro antibacterial and cytotoxicity of resinous endodontic sealers containing calcium hydroxide. Forty rats were implanted with polyethylene tubes containing Sealer 26, Sealer Plus, Dia-ProSeal and an empty tube, examined after 7, 15, 30 and 60 days. Antimicrobial activity was evaluated against Enterococcus faecalis by Agar Diffusion Test (ADT) through inhibition zones. For cytotoxicity, undifferentiated pulp cells (OD-21) were cultured and assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, exposed to dilution of serial extracts at 6, 24, 48h. Cytotoxicity was analyzed by two-way ANOVA and Bonferroni correction. Kruskal-Wallis test followed by Dunn test was performed for nonparametric data (p<0.05). MTT assay revealed cell proliferation affected by sealers extract in all periods (p<0.0001), except for Dia-Proseal and Sealer Plus ⅛ dilution. Subcutaneous analysis showed at day 7th moderate inflammatory infiltration. After 30 days, Sealer 26 still showed moderate inflammatory infiltrate compared to mild inflammation from control and Dia-ProSeal (p = 0.006). At day 60th, all groups showed similar mild inflammatory infiltrate (p>0.05). Sealer 26 induced more biomineralization than other sealers in all periods. At 7 and 15 days, all sealers had significant percentage of immature collagen fibers. After 60 days Sealer 26 showed more mature fibers compared to other sealers (p<0.001). All sealers had a smaller zone of inhibition than chlorhexidine, but with no significant difference among any group (p>0.05). All sealers showed satisfactory biological responses with in vitro/in vivo biocompatibility and antimicrobial activity against planktonic bacteria. Sealer 26 induced more biomineralization than Sealer Plus and Dia-ProSeal.

Postoperative pain after root canal filling with bioceramic sealers: a systematic review and meta-analysis of randomized clinical trials.

The aim of this systematic review and meta-analysis (SRM) was to assess postoperative pain (PP) after endodontic treatment with bioceramic root canal sealer compared to AH Plus® sealer. This SRM was carried out in accordance with the items on the PRISMA 2020 checklist and Cochrane guidelines and registered in PROSPERO (CRD42021259283). Only randomized clinical trials (RCTs) were included. Meta-analysis was conducted using R software, the standardized means difference (SMD) measure of effect was calculated for quantitative variables, and the odds ratio (OR) for binary variables. The Cochrane tool (RoB 2.0) was used to assess the risk of bias, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the quality of evidence. Qualitative and quantitative analysis included 18 and 17 studies, respectively. For quantitative variables, the bioceramic root canal sealer presented less occurrence of postoperative pain than the AH Plus® sealer in 24 h (SMD - 0.17 [- 0.34; - 0.01], p = 0.0340). For binary variables, there was no difference observed between the sealers evaluated, except for sealer extrusion where the bioceramic group had lower post-filling material extrusion (OR 0.52 [0.32; 0.84], p = 0.007). Regarding the risk of bias analysis, low risk was observed for most domains, except allocation that was considered unclear, while the certainty of evidence ranged from moderate to low. The results showed that bioceramics sealers reduced postoperative endodontic pain only after 24 h and showed less sealer extrusion compared to the AH Plus® sealer. However, more robust and standardized clinical trials are needed to confirm the results with less heterogeneity and higher quality of evidence.

Modulatory influence of melatonin on apical periodontitis in Wistar rats fed a high-fat diet.

OBJECTIVE: This study aimed to evaluate the influence of high-fat diet (HFD) and melatonin (MEL) treatment on the progression of inflammation and alveolar bone resorption (ABR) in rats with AP. DESIGN: Forty male Wistar rats were divided into four groups: apical periodontitis (AP), HFDAP, APMEL and HFDAPMEL. The animals were fed an HFD or standard diet for 107 days. On the 7th day, the rats were subjected to AP, and after 70 days, the rats in the MEL groups were treated with MEL for 30 days. Post treatment, the animals were euthanized, and their jaws were retrieved for evaluation of bone resorption, intensity of the inflammatory response, and immunohistochemical analysis including tartrate-resistant acid phosphatase (TRAP) and interleukin-1ß (IL-1ß) levels and tumor necrosis factor (TNF)-α expression. RESULTS: The APMEL group showed reduction in the inflammatory infiltrate and IL-1ß expression relation to HFDAP, while the TNF-α levels did not differ among the groups. The HFDAP group showed an increase in the ABR. MEL reduced the TRAP levels in the APMEL and HFDAPMEL groups. CONCLUSIONS: while MEL could reduce TRAP levels in the APMEL and HFDAPMEL groups, the reduction in the HFDAPMEL group was smaller than that in the APMEL group, demonstrating that the interaction between AP and HFD decreased the anti-resorptive effects of MEL.